Hi, I own a lawn service in Alabama and I had a lot of headaches over weeds. A friend of mine turned me onto a chemical called ARSENAL. This is not an over the counter weed killer. I think the Foresters use this to kill the weeds. This is the best I have ever seen. It will kill weeds in a gravel driveway for up to 1 1/2 years from 1 application. It is enviroment friendly too. Look aroound and see if you can find it. Try your local Farmers Co-op.